meteōrologia

Greek meteōros meant raised up or suspended in mid-air, and logos meant study or discourse. Meteōrologia appeared in Aristotle's 340 BCE treatise examining atmospheric phenomena: clouds, rain, snow, wind, thunder, lightning, rainbows, halos, comets, and earthquakes. Aristotle treated all these as the product of exhalations from the earth — one moist, one dry — rising into the atmosphere. His physics was wrong, but his project of systematic observation was right.

Aristotle's Meteorologica was the authoritative text on weather for nearly 2,000 years. It was translated into Arabic by Hunayn ibn Ishaq in the 9th century CE and transmitted to medieval Europe via Latin translations in the 12th century. Roger Bacon cited it in the 1260s. Even in 1600, European universities were still teaching Aristotle's exhalation theory of weather.

Evangelista Torricelli invented the barometer in 1643, creating the first instrument for measuring atmospheric pressure. Blaise Pascal carried a barometer up the Puy de Dôme in 1648, proving that air pressure decreased with altitude. These experiments broke the 2,000-year grip of Aristotle's Meteorologica and began quantitative meteorology.

Modern numerical weather prediction — the computational process that generates every weather forecast — began with Lewis Fry Richardson's 1922 book Weather Prediction by Numerical Process. Richardson imagined a 'forecast factory' of 64,000 human computers working simultaneously. The actual forecast factory — a supercomputer — arrived in 1950, when the first computerized weather forecast was run on the ENIAC.